1. Field of Invention
The invention relates to an electrical supply or connecting terminal with a clamping spring and with a metal part, the clamping spring and the metal part being located in an insulating housing which has an inlet conductor opening for entry of an electrical conductor which is to be connected, the clamping spring having a clamping leg and a contact leg, and the clamping leg and the metal part forming a spring force clamp connection for the electrical conductor to be connected.
2. Description of Related Art
Electrical terminal means or connecting means are used to establish an electrical terminal or electrical connection, specifically to produce an electrically conductive connection, a metallic connection, between a contact element and a mating contact element. Whether in the individual case there is a terminal means or a connecting means, is functionally relatively unimportant. It is often considered a terminal means when something locally movable is connected to something locally stationary, while often it is considered a connecting means when something locally movable is connected to something locally movable or even when something locally stationary is connected to something locally stationary.
The initially described supply terminal is known, for example, from German Patent Application DE 101 03 107 A1. In the known supply terminal, the metal part is made as a repeatedly bent contact element that has a first profile section which runs essentially perpendicular to the insertion direction of the conductor which is to be connected, with a plug opening for the conductor which is to be connected, and a second profile section which is bent away from it in the insertion direction. The clamping spring, is essentially U-shaped and projects with its clamping leg through the plug opening in the contact element so that the end of the clamping leg presses an electrical conductor which has been inserted into the plug opening against the second profile section of the contact element. The contact element and the clamping spring thus form a spring force clamp connection for an electrical conductor which is to be connected.
The clamping spring is connected to the contact element by the end of the second leg of the clamping spring being riveted securely to the contact element above the plug opening. In the known supply terminal, the fixing of the clamping spring to the contact element by means of riveting is comparatively involved. Moreover, the size of the known supply terminal is relatively large, in particular, the supply terminal is relatively tall since, by fixing the second leg of the clamping spring above the plug opening, the rear spring arc of the clamping spring is also located essentially above the approximately L-shaped contact element.
German Patent Application DE 196 54 611 A1 and corresponding to U.S. Pat. No. 5,975,940 disclose an electrical connecting terminal which also has an essentially U-shaped, open clamping spring and a conductor rail piece which is made as an angle bracket. The conductor rail piece has a retaining leg which is located perpendicular to the conductor entry direction, and a contact leg. In the retaining leg, a rectangular opening is formed through which the electrical conductor which is to be connected can be inserted. The U-shaped clamping spring, with the ends of its legs, is inserted and held in the opening such that the rear spring arc of the clamping spring in the conductor entry direction is located in front of the opening and the clamping leg of the clamping spring presses the inserted electrical conductor against the contact leg, so that, in this known plug-in connector, the clamping spring and the conductor rail piece also form a spring force clamp connection.
European Patent Application EP 1 391 965 A1 and corresponding U.S. Pat. No. 6,814,608 disclose a spring force clamp connection for an electrical conductor having a U-shaped clamping spring and a conductor rail piece. The conductor rail piece is made of a flat material and has a conductor insertion opening in the form of a rectangular material passage which has a perforated collar which extends in the conductor insertion direction and which together with the end of the clamping leg of the clamping spring forms the clamping site for the electrical conductor. In this conductor rail piece which is made as a flat current bar the clamping spring is inserted with the ends of its legs into the conductor insertion opening. When the clamping spring is opened, there is the danger that the clamping spring will slip or with the ends of its spring leg will even slip out of the opening so that proper positioning of the clamping spring, and thus, reliable contact-making of the electrical conductor, are no longer guaranteed under certain circumstances when an electrical conductor is being inserted.
Similar electrical supply terminals with an essentially U-shaped clamping spring and a metal part are known from German Utility Models DE 203 12 861 U1 and DE 202 10 105 U1. It is common to all these known supply terminals that the clamping spring is inserted in an opening of the metal part so that, when the clamping spring is opened, there is the danger that the clamping spring will slip.
In addition, loop-shaped clamping springs are also known in electrical supply or connecting terminals from the prior art, for example, from German Patent Application DE 197 11 051 A1 or German Patent DE 198 02 945 C2, specifically, as so-called tension springs in tension spring terminals. Tension spring terminals have become established on the market over time, in addition to screw terminals and recently also in addition to electrical terminals with insulation piercing terminal technology, and have been used millions of times especially as modular terminals. The advantage of tension spring terminals as compared to screw terminals consists in that the tension spring terminals enable faster and easier wiring. To actuate a tension spring terminal, only one actuating tool is necessary, for example, a screwdriver, which is pressed into the actuating shaft to open the terminal. In doing so, the tip of the screwdriver tensions the tension spring, by which the clamping site is opened. A conductor which is to be connected can then be inserted through the recess into the clamping leg, and it is clamped by the lower edge of the recess again a conductor rail which is connected to the tension spring after pulling out the screwdriver.
One special embodiment of a tension spring terminal is known from German Patent DE 35 14 099 C2 and corresponding U.S. Pat. No. 4,768,981. This tension spring terminal, besides a loop-shaped tension spring, has a specially made conductor rail with two lateral edges so that the conductor rail runs spaced apart from the contact leg of the tension spring. In this tension spring terminal, besides a connection of a flexible conductor in a recess in the clamping leg, in addition, a solid conductor can be pushed between the contact leg and the conductor rail. Since only a relatively small clamping force is applied to the solid conductor which is inserted into the terminal parallel to the contact leg and to the conductor rail, the electrical connection is very heavily dependent on the production tolerances and the diameter of the solid conductor.
One development of the tension spring terminal described directly above is disclosed by German Patent Application DE 199 03 965 A1. In this tension spring terminal, two electrical conductors can be inserted from the same side through the opening in the clamping leg, one conductor then being located underneath and one conductor being located above the conductor rail. The conductor which is located above the conductor rail is pressed against the conductor rail by the specially made contact leg of the tension spring.